1. Field of the Invention
The present invention relates to an automatic tent frame having an extension spring extended when an automatic tent is folded, and more particularly, to an automatic tent frame that is capable of preventing an upper coupler and a lower coupler from being rotated with respect to each other or preventing given gaps from being generated on the coupled portions of the upper coupler and the lower coupler even in a case where an automatic tent is not unfolded to its original shape by the reduction of the restoring force of an extension spring and thus falls down due to external impacts like wind, thus preventing support poles supporting main poles from being damaged to extend the life span of the automatic tent frame, and that is capable of reducing the length of a pipe module, while allowing the pipe module to have the same functions as in conventional one, thus upwardly lifting an outer surface of the automatic tent by the reduced length to increase the interior of the automatic tent by a maximum height and providing very pleasant camping in the relatively extended internal space of the automatic tent.
2. Background of the Related Art
Modern people, who want to live comfortably in nature like mountains and river, away from busy schedules, have enjoyed their camping as one of their endevours to improve their quality of life.
Camping means with modern facilities such as a camping car, a forest park, a bungalow and the like have been developed, but among them, one of the best camping means is an automatic tent capable of realizing the real value of nature and learning the wisdom of life in nature.
However, it is not easy to find an appropriate area for camping, install the automatic tent, and remove the automatic tent, and particularly, it is very hard for women or children to do such works. Accordingly, various developments for an automatic tent frame capable of easily installing and removing the automatic tent have been dynamically made as will be mentioned below.
In this case, an automatic tent is a new tent capable of being installed and removed in a rapid and convenient way, and as shown in FIG. 6, the automatic tent T includes an automatic tent frame 1 forming a frame structure thereof and an outer surface 2 fitted to the outside of the automatic tent frame 1 to shield the automatic tent from rain and wind. The automatic tent T is installed by pulling outer surface loops 21 locked onto the automatic tent frame 1 through momentary unfolding of the automatic tent frame 1 and by unfolding the outer surface 2. The automatic tent is also called foldable tent or one touch tent, and one of the main features of the automatic tent T is the completion of installation and removal with a short period of time through just folding or unfolding, thus improving the convenience in use.
Of course, the outer surface 2 of the automatic tent T basically needs a water proofing function according to the exposure to ultraviolet rays and a flame resistance treatment for protecting a user from fire, but the automatic tent frame 1 basically should improve the easiness in the installation and removal of the automatic tent, maintain the stability of the installed tent, and enhance the conveniences in living in the automatic tent.
Recently, there has been proposed Korean Patent No. 10-1191046 entitled ‘automatic tent frame’, issued on Oct. 9, 2012 to the same inventor as the present invention, wherein the conventional automatic tent frame has an extension spring extended when an automatic tent is folded.
Referring to FIGS. 7 to 9, the above-mentioned conventional automatic tent frame will be in detail explained below. The automatic tent frame 500 includes: a pipe module 510 having two pipes having different diameters from each other, the small diameter pipe being insertedly fitted to the large diameter pipe in such a manner as to slidingly move therein; an upper coupler 520 located on top of the pipe module 510 in such a manner as to be coupled to any one of the two pipes of the pipe module 510; a lower coupler 530 located on the underside of the pipe module 100 in such a manner as to be coupled to the other pipe of the pipe module 510; an extension spring T inserted into the pipe module 510 in such a manner as to be fixed on the upper end periphery thereof to the pipe to which the upper coupler 520 is fixed and on the lower end periphery to the pipe to which the lower coupler 530 is fixed, the extension spring T being fixed in a state of being extended by a given length; a plurality of main poles F9 hinge-coupled to the upper coupler 520; and a plurality of support poles F10 each having one end hinge-coupled to the main pole F9 and the other end hinge-coupled to the lower coupler 530, wherein the extension spring T has an upper coupling end U and a lower coupling end L on which fastening holes H are formed, the upper end periphery of the extension spring T being fixed to the pipe to which the upper coupler 520 is fixed by means of a fastening member M passing through the upper coupler 520 and the pipe to which the upper coupler 520 is fixed in such a manner as to be inserted into the fastening hole H of the upper coupling end U, and the lower end periphery of the extension spring T being fixed to the pipe to which the lower coupler 530 is fixed by means of a fastening member M passing through the lower coupler 530 and the pipe to which the lower coupler 530 is fixed in such a manner as to be inserted into the fastening hole H of the lower coupling end U, and the lower coupler 530 has a through hole P formed on the underside thereof, the lower coupling end L of the extension spring T having an extension piece E exposed to the outside through the through hole P in such a manner as to allow the extension spring T to be extended by a given length L5 in an arrow direction C when the lower coupling end L of the extension spring T is fixed.
According to the above-mentioned conventional automatic tent frame, in the state where the extension spring is extended while the automatic tent frame is being not used for a long period of time, even if the automatic tent is unfolded, it can be completely unfolded to its initial expected shape.
As the time has passed, however, the extension force of the extension spring becomes weak, and further, the restoring force of the extension spring becomes reduced, so that the automatic tent is not unfolded to its initial shape and thus falls down due to the external impacts like wind. Furthermore, the upper coupler and the lower coupler are rotated with respect to each other, and given gaps are undesirably generated on the coupling portions of the upper coupler and the lower coupler, thus causing the support poles supporting the main poles to be turned and damaged to shorten the life span of the automatic tent frame. Accordingly, separate locking means should be needed.
Additionally, the height of the head portion formed by coupling the upper coupler, the pipe module and the lower coupler with each other is relatively high in the whole height of the installed automatic tent, but the height of the internal space of the automatic tent is not relatively high, which causes many inconveniences in standing or moving in the interior of the automatic tent.